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Sire M2 2nd Gen, 3-way miniswitch humbucker mod, tutorial (serial/single coil/parallel - wiring)

A fellow TBer asked me for my wiring on the Sire M2 2nd Gen so I wrote this little tutorial in case somebody else wants to do this great mod to their M2 2nd Gen. This mod will add 2 extra switches to your bass, each controlling one pickup, so you can freely choose between parallel/single coil/serial operation of each humbucker (just like the M7). This results in 15 different combinations of unique sounds just by using the switches and swapping between neck, middle and bridge position. IMPORTANT: the middle position when using both pickups as single coils is not humcancelling, I don't want anyone to be disappointed by the end of this so I'm telling you upfront. I personally have not found this to be an issue since the M2 is shielded pretty well, so I haven't tried rewiring it to make it humcancelling, but be warned of this quirk if you follow my tutorial exactly.

You need to buy two 3-way on/on/on miniswitches, I found a set of three salecom switches on amazon for 15€. on/off/on switches (which are more common) will not work, and obviously they need to be the types you see here with a total of 6 connectors. And annoyingly there are 2 types of switches out there: Type 2 is more common afaik and what I used, but type 1 also exists and in that case you need to mirror the wiring on the switch. Anyway, you just take a multimeter, set it to continuity and make sure that the contacts of the switch which are connected with the lines in this diagram show continuity in each position. If they do and nothing else is showing continuity you can be sure that your switch is the correct kind and you know which type it is:
switch_types.png


The next step is cutting or desoldering the pickup wires from the small PCB in the bass, make note which pickup is connected to what set of pads, but if I remember correctly the ones labeled pick2 are for the neck pickup and pick1 is the bridge pickup.

If you have a type 2 switch, like me, you follow this wiring diagram to wire up each pickup:
M2_pickup_wiring.png


if you have a type 1 switch it's mirrored and you follow this diagram:
M2_pickup_wiring_mirrored.png


The bare wire coming from the pickup is the wire I labeled "shield", just to make sure that's not confusing anyone.
You do that for each pickup and that just leaves you with the signal and ground wires that you added to each switch, you treat those as if they were the actual pickup wires and wire them up to the little board in your M2 where you desoldered or cut the original pickup wires. The outside pads are where you connect the signal, the inside pads are ground:
IMG_20200514_051300.jpg


and here are 2 pictures of my actual wiring on the switch, again this is for the type 2 switch. For the red wire you leave it longer and remove the insulation around it so you can pull it through the first contact and then through the second, make sure the now bare wire isn't touching anything and then just solder it on both connectors:
IMG_20200514_051435.jpg

IMG_20200221_113333.jpg


And lastly, here is the shortest possible demo with sound samples, N stands for neck pickup, B stands for bridge pickup, se is serial, si is single coil and pa is parallel. As I said, 15 different sounds in the following order:

Nse | Nsi | Npa | Bse | Bsi | Bpa | Nse Bse | Nse Bsi | Nse Bpa | Nsi Bse | Nsi Bsi | Nsi Bpa | Npa Bse | Npa Bsi | Npa Bpa

Recorded straight into my audio interface, active mode, every active control at the center detent and volume and tone blend 100% open of course.
In the standard configuration you only have the 3 distinct souds (not counting blending the pickups together obviously) Npa | Npa Bpa | Bpa, I'm personally a huge fan of Nse Bsi or Nsi Bse. Nsi Bpi approximates a jazzbass fairly well and sounds great for slap. The real beauty with that setup, in my opinion, is that you can alter your sound before actually adjusting your EQ. So if I run the standard configuation of Npa Bpa but I lack some low mids, some oomph, I'll probably switch the neck pickup to serial mode. Then, depending on whether I want a more open or more focused sound I can switch the bridge pickup to single coil or leave it set to parallel, etc.
 

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Awesome tutorial, thanks! This functionality is the feature that has me tempted to buy an M7 instead of an M2, this could save me a ton of money without huge effort. Hmmmm.

J.Ja

That was my reasoning for doing this mod as well. I really like the sound of the M2 pickups (I thought I would upgrade them but it's not necessary) and since the pre-amp is the same they are a great deal over the M7. The soldering on the switch itself is a bit finicky but besides that it really is a simple mod.
 
This thread would help for humcancelling wiring:
Series/Single Coil/Parallel Issue, Help Please!!!!

I just tested my own bass and you're completely right, the single coil that is selected is the south coil (the one closer to the bridge) on both pickups. Going by your advice in the thread you posted the red pickup wire would have to be swapped with the black, and the green with the white on one switch to make it humcancelling in the middle position.
Swapping the wiring in the neck PU switch would result in the outer coils being selected and swapping the wiring on the bridge PU switch would give you both inner coils.
As I said, it's not bothering me at all so I won't make the change to the wiring myself but it's a great addition if someone else wants to mod their bass. Thanks.
 
Great Stuff. Thanks for this. Have been doing some easier wiring than this on a different Bass. Will get some more practice on my Soldering before I venture this on my beloved M2. Or I might ask my local guitar wiring Guru for a quote along with a copy of your excellent guide.
 
Just sharing my experience. I left the volume and tone board in place (this was a big uncertainty for me going into it) and wired in an Aguilar obp3 and Nordstrand pickups. Also wired in a serial/single/parallel switch for both piclips and left the passive switch in place. Thing is a beast. I like how it feels and it sounds amazing. Also did a cap swap to get a more effective tone knob.

Eventually, I will need to swap out the passive switch because it’s only a 3 prong switch - as a result the battery engages regardless of whether you’re in passive or active.

IMG_2426.jpeg
 

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